<?php
    // +----------------------------------------------------------------------
    // | ThinkPHP [ WE CAN DO IT JUST THINK ]
    // +----------------------------------------------------------------------
    // | Copyright (c) 2006~2017 http://thinkphp.cn All rights reserved.
    // +----------------------------------------------------------------------
    // | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
    // +----------------------------------------------------------------------
    // | Author: liu21st <liu21st@gmail.com>
    // +----------------------------------------------------------------------
    namespace think;

    use think\db\Connection;
    use think\db\Query;

    /**
     * Class Db
     * @package think
     * @method Query table(string $table) static 指定数据表（含前缀）
     * @method Query name(string $name) static 指定数据表（不含前缀）
     * @method Query where(mixed $field, string $op = null, mixed $condition = null) static 查询条件
     * @method Query join(mixed $join, mixed $condition = null, string $type = 'INNER') static JOIN查询
     * @method Query union(mixed $union, boolean $all = false) static UNION查询
     * @method Query limit(mixed $offset, integer $length = null) static 查询LIMIT
     * @method Query order(mixed $field, string $order = null) static 查询ORDER
     * @method Query cache(mixed $key = null, integer $expire = null) static 设置查询缓存
     * @method mixed value(string $field) static 获取某个字段的值
     * @method array column(string $field, string $key = '') static 获取某个列的值
     * @method Query view(mixed $join, mixed $field = null, mixed $on = null, string $type = 'INNER') static 视图查询
     * @method mixed find(mixed $data = null) static 查询单个记录
     * @method mixed select(mixed $data = null) static 查询多个记录
     * @method integer insert(array $data, boolean $replace = false, boolean $getLastInsID = false, string $sequence = null) static 插入一条记录
     * @method integer insertGetId(array $data, boolean $replace = false, string $sequence = null) static 插入一条记录并返回自增ID
     * @method integer insertAll(array $dataSet) static 插入多条记录
     * @method integer update(array $data) static 更新记录
     * @method integer delete(mixed $data = null) static 删除记录
     * @method boolean chunk(integer $count, callable $callback, string $column = null) static 分块获取数据
     * @method mixed query(string $sql, array $bind = [], boolean $master = false, bool $pdo = false) static SQL查询
     * @method integer execute(string $sql, array $bind = [], boolean $fetch = false, boolean $getLastInsID = false, string $sequence = null) static SQL执行
     * @method Paginator paginate(integer $listRows = 15, mixed $simple = null, array $config = []) static 分页查询
     * @method mixed transaction(callable $callback) static 执行数据库事务
     * @method void startTrans() static 启动事务
     * @method void commit() static 用于非自动提交状态下面的查询提交
     * @method void rollback() static 事务回滚
     * @method boolean batchQuery(array $sqlArray) static 批处理执行SQL语句
     * @method string quote(string $str) static SQL指令安全过滤
     * @method string getLastInsID($sequence = null) static 获取最近插入的ID
     */
    class Db {
        //  数据库连接实例
        public static $queryTimes = 0;
        // 查询次数
        public static $executeTimes = 0;
        // 执行次数
        private static $instance = [];

        public static function __callStatic($method, $params) {
            // 自动初始化数据库
            return call_user_func_array([
                                            self::connect(),
                                            $method
                                        ], $params
            );
        }

        /**
         * 数据库初始化 并取得数据库类实例
         * @static
         * @access public
         * @param mixed       $config 连接配置
         * @param bool|string $name   连接标识 true 强制重新连接
         * @return Connection
         * @throws Exception
         */
        public static function connect($config = [], $name = false) {
            if (false === $name) {
                $name = md5(serialize($config));
            }
            if (true === $name || !isset(self::$instance[$name])) {
                // 解析连接参数 支持数组和字符串
                $options = self::parseConfig($config);
                if (empty($options['type'])) {
                    throw new \InvalidArgumentException('Underfined db type');
                }
                $class = false !== strpos($options['type'], '\\') ? $options['type'] : '\\think\\db\\connector\\' . ucwords($options['type']);
                // 记录初始化信息
                if (App::$debug) {
                    Log::record('[ DB ] INIT ' . $options['type'], 'info');
                }
                if (true === $name) {
                    return new $class($options);
                } else {
                    self::$instance[$name] = new $class($options);
                }
            }
            return self::$instance[$name];
        }

        /**
         * 数据库连接参数解析
         * @static
         * @access private
         * @param mixed $config
         * @return array
         */
        private static function parseConfig($config) {
            if (empty($config)) {
                $config = Config::get('database');
            } elseif (is_string($config) && false === strpos($config, '/')) {
                // 支持读取配置参数
                $config = Config::get($config);
            }
            if (is_string($config)) {
                return self::parseDsn($config);
            } else {
                return $config;
            }
        }

        // 调用驱动类的方法

        /**
         * DSN解析
         * 格式： mysql://username:passwd@localhost:3306/DbName?param1=val1&param2=val2#utf8
         * @static
         * @access private
         * @param string $dsnStr
         * @return array
         */
        private static function parseDsn($dsnStr) {
            $info = parse_url($dsnStr);
            if (!$info) {
                return [];
            }
            $dsn = [
                'type'     => $info['scheme'],
                'username' => isset($info['user']) ? $info['user'] : '',
                'password' => isset($info['pass']) ? $info['pass'] : '',
                'hostname' => isset($info['host']) ? $info['host'] : '',
                'hostport' => isset($info['port']) ? $info['port'] : '',
                'database' => !empty($info['path']) ? ltrim($info['path'], '/') : '',
                'charset'  => isset($info['fragment']) ? $info['fragment'] : 'utf8',
            ];
            if (isset($info['query'])) {
                parse_str($info['query'], $dsn['params']);
            } else {
                $dsn['params'] = [];
            }
            return $dsn;
        }
    }
